blob: 18a5305008791fe4bf9ef4d6eefc70b02b9a81f3 [file] [log] [blame]
smbus.h - SMBus level access helper functions
Copyright (C) 1995-97 Simon G. Vogl
Copyright (C) 1998-99 Frodo Looijaard <>
This program is free software; you can redistribute it and/or modify
it under the terms of the GNU General Public License as published by
the Free Software Foundation; either version 2 of the License, or
(at your option) any later version.
This program is distributed in the hope that it will be useful,
but WITHOUT ANY WARRANTY; without even the implied warranty of
GNU General Public License for more details.
You should have received a copy of the GNU General Public License
along with this program; if not, write to the Free Software
Foundation, Inc., 51 Franklin Street, Fifth Floor, Boston,
MA 02110-1301 USA.
#ifndef LIB_I2C_SMBUS_H
#define LIB_I2C_SMBUS_H
#define I2C_API_VERSION 0x100
#include <linux/types.h>
#include <linux/i2c.h>
extern __s32 i2c_smbus_access(int file, char read_write, __u8 command,
int size, union i2c_smbus_data *data);
extern __s32 i2c_smbus_write_quick(int file, __u8 value);
extern __s32 i2c_smbus_read_byte(int file);
extern __s32 i2c_smbus_write_byte(int file, __u8 value);
extern __s32 i2c_smbus_read_byte_data(int file, __u8 command);
extern __s32 i2c_smbus_write_byte_data(int file, __u8 command, __u8 value);
extern __s32 i2c_smbus_read_word_data(int file, __u8 command);
extern __s32 i2c_smbus_write_word_data(int file, __u8 command, __u16 value);
extern __s32 i2c_smbus_process_call(int file, __u8 command, __u16 value);
/* Returns the number of read bytes */
extern __s32 i2c_smbus_read_block_data(int file, __u8 command, __u8 *values);
extern __s32 i2c_smbus_write_block_data(int file, __u8 command, __u8 length,
const __u8 *values);
/* Returns the number of read bytes */
/* Until kernel 2.6.22, the length is hardcoded to 32 bytes. If you
ask for less than 32 bytes, your code will only work with kernels
2.6.23 and later. */
extern __s32 i2c_smbus_read_i2c_block_data(int file, __u8 command, __u8 length,
__u8 *values);
extern __s32 i2c_smbus_write_i2c_block_data(int file, __u8 command, __u8 length,
const __u8 *values);
/* Returns the number of read bytes */
extern __s32 i2c_smbus_block_process_call(int file, __u8 command, __u8 length,
__u8 *values);
#endif /* LIB_I2C_SMBUS_H */